Adelgids

Adelgids

Adelgids resemble and are closely related to aphids. They attack only conifers. Several important species induce plant gall formation. The most notable of these are the spruce gall adelgids, which induce pineapple-shaped galls on spruce shoots. Some species of adelgids are free living and do not induce galls. The most important of these are the pine bark adelgids, which may occur in large enough numbers to turn the trunks of pine trees white.